Method of forming axle housings



Jan. 24, 1939. J. H. GETTIG METHOD OF FORMING AXLE HOUSINGS Filed March 20, 1937 3 Sheets-"Sheet l Inventor Jan. 24, 1939. J. H. GETTIG 2,145,046

METHOD OF FORMING- AXLE HOUSINGS Filed March 20, 1937 3 Sheets-Sheet 3 v m (9 /z .ticularly directed to the method arms. ,This method of forming Patented Jan. 24, 1939 PATENT OFFICE,

, 2,145,046 METHOD OF FORMING AXLE HOUSINGS Joseph H. Gettig, Buchanan,

Mich., assignor to 1 Clark Equipment Company, Buchanan, Mich.,

a corporation of Michigan Application March 20, 1937, Serial No. 131,991 4 Claims. (01. 29-1534) 'I'his invention relates to axle housings and methods of forming the same, and is more parof. forming a rear axle housing of the type commonly employed in automotive, vehicles, trucks, buses and the like. i

The usual housing employed for this purpose is what is termed a banjo type housinghaving a central enlarged banjo frame section with extending tubular arms terminating in wheel hearing seats or in enlarged brake flanges and bearing have been formed by taking a tubular blank, slotting the same at the'central portion, expanding the central portion to form the banjo frame and swaging down the extending arms to the proper dimensions and upsetting or forgin the wheel bearing seats at the extremities of the the husing-reguires that the tubular blank be of appreciable wall thickness throughout its length and of an appreciable diameter in order to provide sufficient metal for the expansion'of the banjo frame, and thusrequires that the arm portions be swaged down to a smaller diameter to accommodate the wheel bearing seats. The swaging operations are relatively expensive and require considerable time, as well as requiring a considerable investment in equipment.

The primary object of the present invention is to form a housing of this type from a flat rectangular blank of sheet stock or the like, which is operated upon in the flattened condition in such manner as to reduce the thickness of, and increase the area of the central portion while the blank remains flat, and tothen form the blank into tubular shape with the arm sections of the proper diameter and wall thickness, and with the central portion enlarged and slotted for the expanding operation-to complete the banjo frame.

In carrying out the present invention I contemplate taking a flat blank formed from strip stock such as boiler plate or the like, subjecting this blank to a rolling operation which corrugates the central, portion thereof .to produce longitudinally extending corrugations throughout the central portion. The blank thus formed is then subjected to a rolling operation which flattens out the corrugations to produce a laterally enlarged central section of reduced thickness which merges through tapered side edges into the arm portions of the housing. The flat blank thus formed is then slotted in the desired manner by a subsequent rolling operation, and, is then subjected to a transverse 'central tubular section close to those skilled in bending operation to .form

the same into a, tubular shape having arm sections of the proper diameter and wall thickness, and a provided with opposite longitudinally extended slots and of an enlarged diameter and decreased wall thickness. The tubular blank thus formed is then subjected to the usual expanding operations to form-the banjo frame, and the extremities of the arms are then swaged or upset to complete the formation ofv the housing.

One of the main advantages secured by the present process is the elimination of the swaging operations on the arms, and the consequent reduction in cost and labor in producing the completed housing, as well as a considerable saving in the time required for producing the housing.

Another advantage secured by the present invention resides in the fact that the initial operations on the blank prior to the banjo expanding operation can be carried out in rollingoperations which are relatively fast and more economical than previous machine operations for producing the same type of housing. In addition, by the present process the blanks can be continuously fed throughthe corrugating rolls, the flattening rolls, the slotting rolls and thence into the tube shaping machine as acontinuous process, and thus greatly expedite the manufacture of the housing, while reducing the cost and time required as compared to previous operations.

other objects and advantages of the present invention will appear more fully from the following detailed description which, taken in conjunction with the accompanying drawings will disthe art the particular method in which an axle housing of the present invention may be formed.

In the drawings:

Figure l is a plan view of the flat blank after the first corrugating operation thereon;

Figure 2 is an end view of the blank shown in Figure Figure 3 is a plan view of the blank after the rolling operation which has extended its central area andreduced the thickness throughout the central section;

Figure 4 is a sectional blank shown in Figure 3; v

Figure 5 is a view of the blank after the rolling operation which forms the longitudinal slots;

Figure 6 is a sectional view taken substantially on line 6-6 01 Figure 5; a

Figure '7 shows the'blank after it has passed through the preliminary tube forming phase of the process; I

view taken through the Figure 8 is an end view of the blank shown in Figure '1; V

Figure 9 is a elevational view of the blank after it has been formed into tubular shape;

Figure, 10 is a corresponding end view of the blank shown in Figure 9;

Figure 11 is 'an elevational view of one form of housing produced from the blank shown in Figure 9; and p Figure 12 illustra es a second form of housing formed from the blank shown in Figure 9.

Referring nowin detail to the drawings, a flat blank of rectangular shape and of a wall thickness corresponding to that required in the arm sections of the axle housing is cut in sections of suitable length'from flat strip stock or the like. This blank, indicated at in Figure 1, is then passed through a series of corrugating rolls to produce the transverse corrugations 6 in the central portion 1 thereof, these corrugations terminating at approximately the point at which the throats of the completed banjo section will be disposed with reference to the extending arm portions 8 and 9. .By the formation of the corrugations, the wall thickness of the intermediate portion I of the blank is reduced has been displaced in order to provide the increased surface area of the corrugations. The

' corrugated blank shown in Fig. 1 is then passed through suitable rolls which produce the blank shown at III in Fig. 3. This blank has arm sections 8 and 9 which remain the original thickness of the blank 5 as shown clearly in Figure 4,

5 but has a planar central portion 12 of reduced thickness and of increased lateral surface, the

portion l2 having a width substantially greater than the width of the arm sections 8 and 9, and joined to these arm sections by throat portions I3 which are of progressively increasing thickness toward the arm sections as shown clearly in Fig. 4.

The blank formed in the. rolling operation as shown in Figs. 3 and 4 isthen subjected to an additional rolling operation which produces depressed longitudinal portions l4 spaced on opposite sides of the longitudinal center of the portion i2 and extending for a substantial portion of the length of the section I2. Theseportions l4 are closed by thin web sections, indicated at IS in Fig. 6, which, in the expanding operation are lanced and removed in order to accommodate entry of the expanding dies.

It is to be understood that the depressed sec-,

tions M are not pierced entirely through the blank until after the tube forming operation, in order to preserve the strength of this portion and prevent distortion or crushing. This may be optional in the larger sizes of blanks having increased wall thickness. At present, I find it'advisable to perform the flattening operations and the slotting operations as two separate and distinct operations.

The slotted blank, as shown in Fig. 6, may then be passed through the tube forming machine which will shape the blank initially into a substantially semicylindrical section, indicated generally in Fig. 'I, the blank having the extending arm portions 8' and 9' which are of the same wall thickness as the portions 8 and 9 of the blank shown in Fig. 6. The enlarged central portion l2 of the blank shown in Fig. 6 is thus formed into the shape shown in Figs. '7 and 8 with the slots i4 disposed in diametrically opposed relationship centrally of the section [2. The throat portions l3 of the blank shown in Figs. 5 and 6 since the metal form the substantiallyfrusto-conical sections l6 shown in Figsa'l' and 8, by which the thinned wall section of the portion I2 is joined to the thickened arm portions 8' and 9'. This operation upon the blank is accomplished by a series of punch press operations in member is forced against the surface of the blank and bends the blank downwardly into a channelshaped die. opening to form it into the shape shown in Figs. 7 and 8, after which the blank is subjected to a second die operation which closes the upper edges of the blank to produce the completed form of blank shown in Fig. 9.

The blank as shown in Figs. 9 and 10 has the abutting longitudinal edges welded as shown at which a suitable die It by any suitable means such as by atomic hycentral portion i2 is of reduced wall thickness.

and increased diameter so that a smaller displacea ment of metal is necessary to form the completed banjo frame section.

The blank of Fig. 9 is then placed in, suitable expanding die members, substantially as described in Spatta Patent #l,925,850 issued September 5, 1933, and forms a cylindrical banjo section, indicated at 29 in Fig. 11, provided with the radially inwardly extending flanges 22 at opposite sides thereof and joined to the arm portions 8' and S'through' tapered throat portions 23 which progressivelyincrease in wall thickness toward the arms substantially in accordance with the progressive increase in thickness shown'atit in Figs. 4 and 6. The extremities'of the arms 8' and 9 are subjected to successive swaging operations which reduce the external diameter thereof and increase the wall thickness to provide wheel bearing seats, indicated generally at 24',

adapted to support the hubs of wheel spiders wardlyof the brake flanges 25 to form suitable supports for the springs by which the axle is supported from the vehicle.

When a passenger type axle housing is to be provided, the banjo portion provided with the flanges 22 and the throat portion 23 is formed in a manner similar to that described in connection with Fig. 11; and the extending arms 26, corresponding to the arms 8' and 9', are subjected to endwise upsetting operations at their extremities to produce the enlarged thickened radial flanges 21 joined to the ends of the arms by the enlarged annular bearing seat portions 28. The inner surfaces of the portions 28 are suitably machined to receive the bearings for the axle shafts and, if so desired, suitable spring iorming an axle housing of the banjo type which eliminates the swaglng operations heretofore found necessary, and which can readily be designed to provide a continuous process from the treatment of the original flat blank of uniform wall thickness to the formation of the tubular blank having the central portion of increased diameter and decreased wall thickness, with the integral tubular extending arms with the proper external diameter and proper wall thickness.

I am aware that various modifications maybe made in certain phases of the operations described herein, and therefore do not intend to be limited except as defined by the scope and spirit of the appended claims.

I claim:

1. The method of forming an axle housing which comprises providing a flat blank, transversely corrugating the central portion thereof, rolling said corrugations out to produce a central section of enlarged surface and decreased thickness, rolling alined transversely spaced oblong depressions therein on opposite sides thereof, forming said blank into tubular shape, expanding said central section to form a banjo frame section, and forming wheel bearing seats at the extremities .of the blank.

2. The method of forming an axle housing which comprises providing a flat rectangular blank, rolling said blank to produce a series of transversely spaced longitudinally extending corrugations only in the central portion thereof while maintaining the blank uniform in width, flattening the corrugatedportion of said blank to produce a central portion of increased width and decreased thickness merging into theunrolled portions of said blank through intermediate sections of tapering width and thickness, forming said blank into a tube having a central section of enlarged diameter and opposite tubular arms joined thereto through frustoconical sectionjs, and expanding said central section into a circular banjo frame with its axis normal to the axis of said arms.

3. The method of forming a blank for an axle housing which comprises transversely corrugating the central portion of an elongated rectangular sheet, rolling said corrugations out to form a flat sheet having laterally projecting surfaces at opposite sides of the central portion thereof, forming oblong shaped transversely spaced depressions in alined positions in opposite surfaces of said central portion, and forming said sheet into a tubular blank with the opposite longitudi nal edges thereof welded together.

4. In the method of forming an axle housing from a single flat rectangular blank of a uniform thickness equal to that desired in the arm portions of the housing, the novel procedure which comprises transversely corrugating the central portion of the blank and then flattening the same to increase the lateral surface of said portion and thereby decrease its wall thickness, the end portions of said blank merging into said central portion through tapered intermediate portions, and then pressing said blank into tubular shape with said central portion forming a cylinder of increased diameter merging through intermediate frusto-conical sections of progressively increasing. thickness into oppositely extending arm portions.

JOSEPH H. GET'I'IG. 

